In concomitance with the development of electronic techniques in recent years, a reduction in size and an increase in capacity of electronic components, such as a multilayer ceramic capacitor, have been rapidly advanced.
In this type of electronic component, such as a multilayer ceramic capacitor, in general, after an external electrode-forming conductive paste is applied onto two end portions of a base component in which internal electrodes are embedded, external electrodes are formed by a firing treatment, and furthermore, in order to improved heat resistance and solder wettability of the external electrodes, plating films of Ni, Sn, solder, and/or the like are formed on the surfaces thereof so as to cover the external electrodes.
In addition, Patent Document 1 has proposed a multilayer ceramic capacitor in which a base component includes a CaZrO3-based compound as a primary component, external electrodes each include a glass frit and a metal powder containing one of Cu, Ni, and a Cu—Ni alloy as a primary component, and the glass frit includes 8 to 36 percent by mole of B2O3, 31 to 62 percent by mole of SiO2, 9 to 43 percent by mole in total of at least one of an alkali metal oxide and an alkaline earth metal oxide, and 0 to 3 percent by mole of ZnO.
In addition, Patent Document 1 has also disclosed that a penetration distance of a glass phase into the base component is controlled to be 1 to 8 μm.
In Patent Document 1, since a borosilicate zinc-based glass having the above molar composition is contained in the external electrode, the glass phase can be appropriately penetrated into the base component. By this penetration described above, it is intended to improve a bonding strength between the base component and the external electrode and plating adhesion properties thereof and also to suppress generation of structural defects of internal electrodes.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2005-228904 (claims 1 and 2, paragraph [0015], and the like)